Rename the Ext2 recognizer to a more generic Ext to be more future-proof with a possible upcoming ext4 support.
Also, it already makes no sense to use the name ext2 as it already recognizes all the FS of the "Ext family".
In addition, add the Ext Recognizer for CDs.
There is no need to compile our DLLs as shared libraries since we are
managing symbols exports and imports through spec files.
On my system, this reduces the configure-time by a factor of two.
